Table 1.

Voigt notation for the contraction of indices: CijklCij:klCLM. The contraction for the first pair of indices ij is shown. That for the second pair, kl is similar. For example, C1231C65.

original indicescontracted indices
i = j = 1, L → 1i = 2, j = 3, L → 4 ← L, i = 3, j = 2
i = j = 2, L → 2i = 1, j = 3, L → 5 ← L, i = 3, j = 1
i = j = 3, L → 3i = 1, j = 2, L → 6 ← L, i = 2, j = 1